1. Technical Field
The present invention relates to a liquid ejection head and a liquid ejection apparatus for injecting liquid and, more specifically, to an ink jet type recording head and an ink jet type recording apparatus for discharging ink as the liquid.
2. Related Art
Various types of ink jet type recording heads, which correspond to a liquid ejection head generally used in printers, facsimile machines, copying machines and so on are known according to the mechanism for discharging ink drops. For example, there are a type in which ink drops are discharged from nozzle openings by employing a diaphragm as part of a pressure generating chamber which communicates with the nozzle openings and expanding and contracting the capacity of the pressure generating chamber by deforming the diaphragm by displacing a piezoelectric element, and a type in which ink drops are discharged from nozzle openings by changing the capacity of a pressure generating chamber by deforming a diaphragm using electrostatic force.
There is an ink jet type recording head in which a piezoelectric element is provided on one side of a flow-channel forming substrate which is provided with the pressure generating chamber in communication with the nozzle openings in an area which opposes the pressure generating chamber via the diaphragm. The flow-channel forming substrate is formed with an ink supply channel which communicates with one end side of the pressure generating chamber in terms of the longitudinal direction by reducing the width of the pressure generating chamber in the short side direction thereof and an inclined surface formed by inclining a stepped surface between the pressure generating chamber and the ink supply channel in the direction of the thickness of the flow-channel forming substrate (for example, see JP-A-2005-153243 (pp. 7-10, FIG. 2).
However, even though the stepped surface between the pressure generating chamber and the ink supply channel is formed into the inclined surface as disclosed in JP-A-2005-153243, there remains a problem such that air bubbles entering ink supplied from the side of the ink supply channel may stay at a corner defined by the stepped surface and a side surface of the pressure generating chamber, and when the air bubbles are grown up, the interior capacity of the pressure generating chamber is reduced, so that the ink discharging property may be adversely affected.
There is also proposed a configuration in which the corner of the ink supply channel for supplying the ink to the pressure generating chamber is formed into a curved surface along a crystal axis (for example, see JP-A-7-178909 (p. 3, p. 5, FIG. 8 and FIG. 16).
However, with the configuration in JP-A-7-178909, there remains a problem such that air bubbles entering the ink flowing through the ink supply channel cannot be prevented from staying therein.